Locations

The HZI is continuously building a network of closely aligned strategic partnerships with universities, research institutions and hospitals. Its primary objective is to create synergies which establish the optimal conditions for an efficient transfer of knowledge from basic research to medical application: HZI Locations.

The Strategy of the HZI

Learn more about how the HZI, with its translational focus, will help to facilitate a faster and more targeted approach when it comes to fighting and preventing existing, emerging or recurring infectious diseases.

Working at the HZI

Around 900 employees in research, administration and infrastructure, and about 220 visiting scientists from 40 different countries are employed at the Helmholtz Centre for Infection Research. To ensure top quality research we need top quality employees. Your creativity and innovative capabilities are the basis for the long-term success of our work. That's why we undertake a great deal to attract the best people to us. Learn more about this.

Feature

Systems BiologyThe goal of systems biology is to describe the dynamic processes of life and of biological systems using mathematical models. In line with the foundation of the new Braunschweig Integrated Centre of Systems Biology (BRICS) we have compiled some background information about systems biology for you: To the systems biology feature.

How may individualisation find its way into care of patients with infectious diseases? This is the hot topic to be discussed during the international Herrenhausen Symposium on June 21-23, 2018, in Hannover.

When the hunters become the hunted

Braunschweig Helmholtz researchers show how bacteria drive immune cells to death

Helmholtz-HZIStreptococcus pyogenesThe immune system defends the body against pathogens. Macrophages are part of the first line of defence: they identify pathogens that have gained entry and destroy them. Bacteria that infiltrate the body are not powerless to resist the macrophages, however. Substances formed by the bacteria attack the macrophages, an attack that they sometimes fail to survive.

Eva Medina and her Infection Immunology research group at the Helmholtz Centre for

Infection research (HZI) in Braunschweig have discovered a new mechanism that leads to the destruction of macrophages. The results have been published in the current issue of the scientific journal Cellular Microbiology.

Macrophages identify bacteria, fungi and viruses that can make the body ill. They

absorb these germs in order to combat them. Inside the cell they destroy the intruders and use chemical messenger substances to draw further immune cells into the source of infection. If the macrophages are unable to defend themselves against the bacteria, then the bacteria gain the upper hand – the infection spreads.

Eva Medina and her research group at the HZI investigated the manner in which the bacteria

Streptococcus pyogenes attacks the macrophages. The findings came as a surprise to the researchers: the bacteria destroy the power plants of the macrophages, the mitochondria. As a result, energy supplies collapse and the cells die. In their experiments the researchers identified the previously unidentified mechanism that leads to the destruction of the mitochondria and subsequent cell death.

The process commences with substances produced by the bacteria that penetrate the cell walls of the macrophages. "Bacteria produce these so-called cytolysines continuously in order to prepare themselves for meeting our immune defence system," says Eva Medina. The researchers attempted to block the holes in the membrane of the macrophages and thereby save the cells. Although this proved successful, the cells died nevertheless. Medina's team identified the reason for this after some time: the bacteria had not only penetrated the cell wall, in the process they had also damaged the "cell power plants", the mitochondria. "Normally, the macrophages have learned to evade these cytolysines and neutralise them. However, the holes in the membrane trigger stress in the cells and also inhibit the mitochondria inside the cell. Finally, they give up and cease producing energy," says Medina.

That which results in death for the macrophages aids the bacteria in the infection. "The bacteria kill the macrophages insidiously from a distance. The body's first line of defence collapses. The cell death of the macrophages results in tissue damage and the bacteria are able to spread out more easily," says Medina. "By the time the immune system realises that something is wrong, it is too late."